Polishing machine



Dec. 27, 1938. H. s. INDGE 2,142,058

RoLIsHING MACHINE4 Filed Dec. l0, 1957 4 Sheets-Shet 1 d6 n www;

Fig 4 5' 21mm HERBERT ,SINDGE De@ 27, 1938. H. s. INDGE POLISHING MACHINE Filed Dec, l0, 1937 4 Sheets-Sheet 2 HERBERT S. INI/EE Dec. 27, 1938. v H, INDGE 2,142,058

POLISHING MACHINE Filed Dec. l0, 1957 4 Shets-Sheet 3 HERBERT S. INDGE Dec. 27, 1938. H. s. INDGE POLISHING MACHINE Filed Dec.

l0, 1916*?V 4 Sheets-Sheet 4 HERBERT S. .TA/UEE lil Patented Dec. 27, 1938 UNITED STATES PATENT oFFlcE POLISHING MACHINE Application December 10, 1937, Serial No. 179,157

20 Claims.

The invention relates to abrading machines, and more particularly to a polishing machine for polishing spaced cylindrical portions on a work piece.

One object of the invention is to provide a thoroughly practical polishing machine for pol ishing spaced cylindrical portions on a work piece, such as for example a completely assembled motor armature shaft. It is another object of this invention to provide a polishing machine in which the work piece, such as an armature shaft or the like, is supported to rotate an abrasive on an abrasive work support, such as a rigidly supported flexible labrasive element or a bonded abrasive element which serves simultaneously to support and polish the spaced portions on the work piece. A further object of the invention is to provide such a machine with a frictional driving wheel which is arranged frictionally to engage and rotate the work piece during the polishing operation.

A further object of the invention is to provide a polishing machine for polishing spaced cylindrical portions on a work piece while it is supported on an abrasive work supporting member in which the abrasive is formed as a roll of continuous flexible abrasive material which is arranged so that it may be automatically advanced after each polishing operation so as to present a fresh abrading surface for the next work piece to be polished. A further object of the invention is to provide an abrasive work support in which two spaced parallel normallynon-rotatable bonded abrasive elements serve to support and polish a work piece and are automatically .indexed to present a fresh abrasive surface before or after each polishing operation. Other objects will be in part obvious or in part pointed out hereinafter.

The invention accordingly consists in the features of construction, combinations of elements, and arrangements of parts, as will be exemplified in the structure to be hereinafter described, and the scope of the application of which will be indicated in the following claims.

In the accompanying drawings, in which is shown one of various possible embodiments of the mechanical features of this invention,

Fi-g. 1 is a front elevation of the improved shaft polishing machine, having parts of the base broken away and shown in section more clearly to show the driving mechanism;

Fig. 2 is a right end elevation of the machine, having parts broken away and shown in section more clearly to show the driving and operating mechanism; y

Fig. 3 is a plan view of the machine;

Fig. 4 is a fragmentary longitudinal sectional View, taken approximately on the line 4 4 of '5 Fig. 3, showing the mechanism for reciprocating the abrasive supporting carriages;

Fig. 5 is a fragmentary cross sectional View, on an enlarged scale, taken approximately on the line 5 5 of Fig. 4, showing the carriage recipro- 10 eating mechanism and the drive therefor;

Fig. 6 is a fragmentary perspective view, on an enlarged scale, showing the mechanism for automatically actuating the driving clutch;

Fig. 7 is a fragmentary detail elevation of the 15 driving clutch actuating mechanism, taken approximately on the line 'I-'I of Fig. 1;

Fig. 8 is a fragmentary end elevation, on an enlarged scale, of a modified form of abrasive Work support; and

Fig. 9 is a fragmentary end elevation, on an enlarged scale, of a modified form of abrasive work support.

One embodiment of the improved polishing machine for polishing cylindrical work pieces has 25 been disclosed in the drawings comprising a base I Il which supports a .plurality of longitudinally.r reciprocable slidesI or tables II, I2, I3 and I4. In order that the slides II, I2, I3 and I 4 may be reciprocated or oscillated rapidly, an anti-fric- 30 tion bearing support therefor is provided. The base I0 is provided with spaced parallel longitudinally extending V-Ways I5 and I6 each of which supports a row of balls I1 and I 8, respectively. The tables II, I2, I3 and I4 are each 35 provided with a Vway|9 resting on the balls I 'I and a flat way 20 resting on the balls I8 so that the tables II, I2, I3 and I4 may be readily oscillated or reciprocated at a rapid rate.

This machine is particularly intended for the polishing of lspaced cylindrical work pieces on a cylindrical piece of work. For example, in the manufacture of electric motors, it is desirable to put a final polish on the bearing surfaces of the motor shaft after the armature has been completely assembled and the armature is ready 'for installation in the motor. To facilitate polishing such Work pieces at a rapid rate, the improved machine is arranged as a duplex machine, so that while one shaft is being polished, another 50 polished shaft may be removed and a new shaft loaded in place, thereby increasing the output of the machine. To accomplish this result, the pair of tables I I and I2 are utilized to support an armature shaft 2l and the tables I3 and I4 55 are arranged rotatably to support an armature shaft 22. 1

Each of the slides or tables il, l2, I3 and I4 are provided with work supporting brackets 23, 24, 25 and 26, respectively. These brackets are spaced longitudinally from each other and arranged in pairs simultaneously to support spaced portions of a Work piece, such as an armature shaft. In the preferred form, each of the Work supporting brackets 23, 24, 25 and 26 is provided with a pair of spaced parallel rollers 21 and 28 (Fig. 2) which are rotatably supported by a pair of studs 29 and 3U, respectively. The studs 2S and 30 are carried by the bracket 26. The rollers 21 and 28 on the brackets 25 and 26 are arranged to support end portions 35 and 36 of an armature shaft 31 for a polishing operation. Similarly, the corresponding rollers 21 and 28on the work supporting brackets 23 and 24, respectively, serve to support and polish spaced portions 33 and 39 of an armature shaft 46. l,

The work supporting rollers 21 and/ 28 serve as a support for a flexible abrasive element so that when the armature shaft is rotated relative thereto, a polishing operation will be produced on the desired portions of the armature shaft. A continuous Astrip of flexible abrasive material, such as abrasive paper or cloth 45, is provided in the form of a roll 46 rotatably supported on a shaft 41 carried by the base i6. The abrasive paper 45 passes over the upper surfaces of the work supporting rollers 23 and 21 and passes under the same and over a rotatable idler roller 49 and reels up on a spindle 56 which is supported in suitable bearings in the base l0. From this disclosure it will be readily apparent that when a. work piece is placed upon the abrasive paper 45, the weight of the armature shaft or work piece to be polished will cause the paper to wrap around a portion of the work piece and allow it to drop into the position as illustrated in Fig. 2. In this position of the work piece, the work piece is rotated.

Similarly, a roll 46a of flexible abrasive paper l 45a is rotatably mounted on the inner end of the shaft 41 andis arranged to pass over a work supporting element carried by the work supporting member 25. The abrasive strip 45a passes over the rollers 28 and 21 carried by the work supporting member 25 and is wound upon the spindle 50. When a work piece, such as an armature shaft 22, is placed in position with the spaced bearing portions 35 and 36 resting on abrasive .paper 45ay and 45, respectively, the abrasive paper will be depressed'to'wraparound the surface of the portions 35 and 36, so that when the armatureA shaft 22 is rotated, the rotation of the shaft on the abrasive paper surface will be polished to the desired extent.l A similar abrasive paper assembly is provided for the work supporting members 23 and 24. A rotatable shaft 52 is rotatably journalled in suitable bearings in the base l and serves as a support for rolls 53 and 53a of abrasive paper 54 and 54awhich pass over the work supporting surfaces on work supporting members 23 and 24 so as to provide abrasive supports for spaced portions 38 and 33 on the armature shaft 2|.

In the manufacture of electric motors and other similar pieces of apparatus having rotatable elements which rotate at a rapid rate, it is frequently desirable to assemble the rotor on its shaft and to `put a final polish on the bearing surfaces of the shaft after the assembly of the rotor is completed. In such an operation, it is desirable to provide a driving mechanism whereby the rotor land its shaft may be rotated during the polishing operation without the necessity of a clamping d og to drive the same. In the preferred form, a friction work driving wheel 55 is arranged to be moved into frictional contact with the periphery of the armature 31 of the shaft 22 to rotate the same and thereby produce a. polishing action upon the bearing portion on the armature shaft. The friction driving wheel 55 may be of-'any suitable material, such as a bonded abrasive wheel. abrasive covered or coated wheel, a leather covered Wheel, or a rubber Wheel, which when brought into contact with the periphery of the armature 31 will rotate and drive the same. 'Ihe friction wheel 55 is carried by a spindle 56 which is journalled in suitable bearings 51 and 58 which are formed integral with or iixedly mounted on a pivotally mounted arm 59 which is arranged to swing about the axis of the shaft 60 as a pvot so that it may be moved toward and from an operating position to start and stop the rotation of the work piece as desired.

y The Wheel spindle 56 carries at its outer end a multiple V-groove pulley 6I which is connected by V-belts 62 with a multiple V-groove pulley 68 on a shaft 61. The shaft 66 is supported in brackets 4l and 42 which project upwardly from the rear portion of the base l0. A driving motor 63 is mounted on the rear of the base I0. The motor 63 is provided with an armature shaft 64 which carries a multiple V-groove pulley 65. A pair of V-belts 66 engage the center pair of grooves of the pulley '65 and pass around a multiple V-grooved stepped pulley 66 which is fixedly mounted on the rotatable shaft 61. The shaft 61 carries a multiple V-grooved pulley 66 which is connected by V-belts 62 with the pulley 6I on the end of the Wheel spindle 56 so as to transmit a rotary motion from the motor 63 to the frictional work driving wheel 55 to produce a rotation of the work during the polishing operation. The belts 66 may be shifted to other steps on the stepped V-groove pulley to change the speed of the work driving wheel when desired. The motor 63 is preferably mounted so that it may be adjusted in a vertical direction to tension the driving belts 66 as desired and to facilitate changing of driving wheel speeds when desired. The motor 63 is also pivotally mounted so that it may be adjusted about a stud 16 to tension a driving belt 1| to be hereinafter described.

Y A similar work driving unit is provided for rotating the armature shaft or work piece 2i supported on the work supporting members 23 and 24. A work driving Wheel 15 is supported on a -spindle 16 which is journalled in bearings 11 and 18 which are carried by a pivotally mounted arm' 19 which is pivoted to swing about the shaft 6U as a pivot to swing the driving wheel 15 toward or fromv the armature 46 of the armature shaft 2|. The spindle 16 is provided with a multiple V-pulley 8i which is connected by a pair of V- belts 82 with a pulley 83 mounted on the shaft 65.

It is desirable to provide a. stopping and starting mechanism for controlling the rotation of the Work driving wheels and 15. The V-groove pulleys 68 and 83 are preferably rotatably mounted on the shaft 61. In order to transmit the rotary power of the motor 63 to the driving wheels 56 and 15, respectively, a clutch 12 and 13 are interposed between the driven shaft '61 and the pulleys 68 and 83, respectively. The clutches 12 and 13 have not been illustrated in detail, since they are not considered to be a part of the present invention, but merely a conventional showing of a cone and clutch has been illustrated. When the clutch member 12 is moved toward the left (Fig. 3), it is thrown into engagement so that the rotary power of the shaft 61 is transmitted to rotate the pulley 68 which in turn, through the V-belt 62 rotates the work driving wheel 55. Similarly, when the clutch member 13 is moved toward the right (Fig. 3), it is thrown into engagement to lock the pulley 83 to the shaft 61 so that the rotary motion of the shaft 61 is transmitted through the pulley 83 and belt 82 to rotate the work driving wheel 15. A yoke 14 is mounted on the end of a rotatable shaft and is arranged to actuate the clutch 12 when desired. Similarly, a yoked member 9| is mounted on the end of a rotatable shaft 92 and is arranged to actuate the clutch 13 to stop and start the rotation of the work driving wheel 15.

'Ihe abrasive paper becomes worn and A the abrasive particles dulled after a polishing operation. To insure a uniform polishing action on successive pieces of work, it is desirable to provide an automatic indexing mechanism which serves automatically to index the paper to present a fresh abrading surface for each polishing operation. The spindle 50 on which the abrasive paper 45 is arranged is provided with a ratchet wheel 85. A bell crank lever 86 is pivotally supported on the spindle 50 and is provided with a pawl 81 engaging the teeth on the ratchet wheel 85.l The upper end of the vertically slidable rod 88 is arranged in the path of the pivotally mounted arm 59 and its lower end is arranged to engage the bell crank lever 86 so as to actuate the pawl 81. When the arm 59 is swung downwardly into an operating position (Fig. 2), the rod 88 moves downwardly, rocking the bell crank lever 86 in a clockwise direction `to cause an idle movement of the pawl 81 over the teeth of the ratchet Wheel 85. After a polishing operation has been completed and the work driving wheel moved upwardly to an inoperative position, the released compression of a spring pressed plunger 89 serves- A similar automatic indexing mechanism com? prising a pawl and ratchet mechanism (not shown) is provided for automatically advancing the abrasive paper 54 and 54a in timed relation with the movement of the work driving wheel 45 to and from an operating position before and after a polishing operation. It should be noted that the rotation of the work is such that any thrust on the abrasive paper 45 is taken up by the pawl 81 and ratchet wheel 85. The work driving wheel 55 rotates in a clockwise direction, as indicated by the arrow in Fig. 2. This transmits a rotary motion to the armature 31 to rotate it in a counterclockwise direction, thus producing a thrust on the abrasive paper tending to unwind it from the spindle 50.

To facilitate removal of a polished piece of work and insertion of a new piece of work, it is desirable to provide a suitable mechanism for moving the work driving wheel to and from an operating position. In the preferred form, a fluid pressure mechanism is mechanically connected so that the swinging arms 59 and 19 may be readily and independently rocked to and from an operating position. As illustrated in the drawings, a toggle lever mechanism is provided comprising a toggle lever 94 which is pivotally connected by a stud 95 with the arm 59. A second toggle lever 96 is rotatably supported on a shaft 91 which is journalled in suitable bearings 98 on the base |0 of the machine. The adjacent ends of the toggle levers 94 and 96 are pivotally connected together by means of a stud 99. The toggle lever 98 is preferably formed as a bell crank lever having a downwardly projecting arm |00 which is connected by a stud |0| with the outer end of a piston rod |02. A piston |03 is xedly mounted on the inner end of the piston rod |02 and is slidably mounted within a uid pressure cylinder |04.' In order to prevent free movement of the bell crank lever, the cylin'- der |04 is preferably pivotally supported so that it may readily swing as the parts move. The cylinder I 04 is pivotally connected by means ,of a stud |05 which is in turn supported by a bracket |06 which is formed integral with the base |0.

It is desirable to provide a suitable fluid pressure system including a control apparatus, whereby uid under pressure may be readily admitted to either end of the cylinder |04. A fluid pressure system has been illustrated comprising a iluid reservoir |09 which is formed integral within the base |0. A fluid pump ||0 pumps iluid from the reservoir |09, through a pipe and forces fluid under pressure through a pipe I2 to a control valve ||3. A pipe ||4 connected with the pipe ||2 is provided with a pressure relief valve ||5 which is preferably of the adjustable type, so that a desired pressure may be maintained Within the fluid pressure system. If the pressure within the system builds up over the desired pressure, the relief valve 5 opens, thus conveying excess fluid under pressure to the reservoir |09.

The control valve ||3 is preferably a balanced piston type valve comprising a valve stern ||6 having formed integrally therewith valve pistons 95 and 91V so as to swing the arm 59 and the work driving wheel 55 into operative frictional engagement with the periphery of the armature 31 to rotate the armature and its supporting shaft 2| and to cause a relative rotation between the exible abrasive element and the spaced bearing portions on the shaft to be polished. During the movement of the piston |03 toward the right (Fig. 2) to swing the'work driving wheel 55 into operative contact with the armature, fluid within a cylinder chamber |22 is exhausted therefrom through a pipe |23 into a valve chamber between the valve pistons 8 and ||9 and out through a pipe |24 into the reservoir |09.

The valve ||3 is preferably manually controlled by means of a manually operable lever |25 which `is pivotally mounted on a stud |26 supported in valve stem 6. The lever |25 is provided with an enlarged portion |28 (Fig. 1) which has an elongated aperture therein which straddles a spool-shaped member |29 mounted on the outer end of the valve stem |26. The lever |25 is provided with a pair of inwardly projecting pins |30 which ride within the groove of the spool shaped member |29 so that when the control lever |25 is rocked about its supporting stud |26 is a pivot, the valve st em will be shifted to control the direction of flow of fluid to and from the cylinder After the bearing portions 35 and 36 on the armature shaft 22 have. been polished to the desired extent, the control lever |25 is rocked in a clockwise direction to cause the valve stem ||6 to move toward the left (Fig. 2), thus shifting the valve pistons ||1, ||8 and ||9 so as to reverse the flow of fluid to and from the cylinder |04. In the new position of th'e valve, fluid under pressure from the pipe ||2 enters a valve chamber formed between the valve pistons ||8 and ||9 and passes through the pipe |23 into the cylinder chamber |22 to cause the piston |03 to move toward the left (Fig. 2). This movement causes the bell crank arms and 96 to rock in a clockwise direction,'thus rocking the toggle lever 94 in a counterclockwise direction until the toggle levers 94 and 96 approach a straight line position, thus rocking the arm 59 in a clockwise direction to swing the work drivlng wheel 55 to an inoperative position to facilitate removal of the polished piece of work and the insertion of a new piece thereinstead.

During the movement of the piston |03 toward the left (Fig. 2) fluid within the chamber |2| is exhausted through pipe |20, into the valve chamber between the valve pistons |I1 and ||8, and out through the pipe |24, into the reservoir |09.

A similar fluid pressure piston and cylinder actuated toggle lever mechanism is provided to swing the arm 19 to move the work driving wheel 15 to and from an operating position. Each of these mechanisms is independently controlled so that while one of the mechanisms is in an operative position, the other may be in an inoperative or loading position. A toggle lever |35 is pivotally mounted by a stud |36 to the arm 19. A bell crank lever having an upwardly extending arm |31 is pivotally mounted on the shaft 91 and is` connected by a stud |39 with the lower end of the toggle lever |35. The bell crank |31 is provided with a downwardly extending arm |40 which is connected by a stud |4| with a piston rod |42 which is connected with a piston (not shown) Within a cylinder |43 'Ihe cylinder |43 is pivotally supported in a manner similar to that shown for the cylinder |04. A manually operable control lever |45 is pivotally supported by a stud |46 to a bracket |41 supported on the base |0. The lower end of the lever |45 is provided with an enlarged portion |48 which is connected to move a valve stem |49 of a control valve (not shown). The control valve together with the cylinder |45 is identical with that previously described and it is, therefore, believed it is not necessary to illustrate this contruction in detail. By manipulation of the control lever |45, the driving wheel 15 may be moved to and from an operating position independently of the movement of thedriving wheel 55.

Reciprocating `mechanism.

In order to prevent rings being formed around the periphery of the work due to single abrasive grains scoring the work during the polishing operation, it is desirable to provide a relative reciprocating movement between the abrasive element and the shaft to be polished so as to provide not only a rotary but a relative reciprocatory movement between the abrasive element and the shaft being polished. This is preferably accomplished by reciprocating the abrasive supporting elements simultaneously in opposite directions, thereby counteracting any tendency yto shift the work piece longitudinally relative to the work driving wheel. As illustrated in the drawings, a rotatable shaft |15 is journalled in suitable bearings |16, |11 and |18 in the base I0. The shaft |15 carries a pair of eccentrics |19 and |80. The eccentric |19 is connected by a link |8| with a stud |82 which is carried by a rock arm |83, the lower end of which is pivoted by a stud |84 to the base |0. The upper end of the rock arm |82 is provided with a stud |85 which carries a square shaped bushing |86. The square shaped bushing |86 is slidably supported in a vertical slot which is cut in a depending projection |81 on the under side of the table I4.

Similarly, the eccentric |90 is connected by a link |90 with a stud |9| carried by a rock arm |92, the lower end of which is pivoted by a stud |93 to the base I0. The upper end of the rock arm |92 is provided with a stud |94 which carries a square shaped block |95. 'I'he block |85 slides in a vertically extending slot in a depending projection |96 on the under side of the table i3. It is readily apparent from the foregoing disclosure that motion transmitted by the eccen-V trics |19 and |80 is transmitted through the connecting links |8| and 90, respectively, to rock the rock arms |83 and |92, respectively, and thereby to reciprocate the tables |4 and I3, respectively, simultaneously and in opposite directions. Due to the sliding connection between the square shaped bushings |86 and |96 within the downwardly extending projections |81 and |96 of the tables 4 and I3, respectively, a reciprocatory motion may be transmitted to said tables without the tendency of lifting the tables from their supporting ways.

The tables or slides and |2 are similarly provided with a reciprocating mechanism comprising a s haft 200 (Fig. l) which carries a pair of eccentrics 20| and 202 which are connected by links 203 and 204, respectively, to rock arms 205 and 206, respectively. The rock arms 205 and 206 are pivot-ally connected by means of stud 201 and 208, respectively, on the base |0. The upper ends of the rock arms 295 and 206 are connected by means of slidably mounted square shaped bushings 209 and 2|0, respectively, with the tables and |2, respectively. Rotation of the shaft 200 and eccentrics 20| and 202 serves simultaneouly to transmit a reciprocatory movement to the tables and |2 simultaneously to reciprocate them in the opposite direction, so that the reciprocatory movement of one neutralizes the movement of the other upon the work piece so that the work piece will be maintained against an endwise movement.

In order to drive the reciprocating mechanism, a V-belt 1| transmits power from the motor pulley 65 to a pulley 2|5 which is mounted on a bushing 2 |6 which is in turn rotatably supported on a shaft 2|1. The shaft 2|1 is rotatably supported in anti-friction bearings 2|8 and a similar anti-friction bearing (not shown) contained within the projecting boss 2|9 of the base I0. The shaft 2|1 is provided with a pulley 220 mounted n its outer end which is connected by means of a V-belt 22| with a V-groove pulley 222 which is mounted on the outer end of the shaft |15. In order to transmit power from the pulley 2|5 to the shaft 2|1, a friction disk clutch 223 is interposed therebetween. A yoked member 225 carried by a shaft 226 and arranged to move a spool-shaped member 221 serves to engage or disengage the clutch 223 to start or stop the rotation of the shaft |15 and thereby to control the starting and stopping of the reciprocatory movement of the tables I3 and |4.

To facilitate loading of work pieces and removal of work pieces to and from the machine, it is desirable that the reciprocation of the abrasive work supports be stopped when the Work driving wheel is moved to an inoperative position. In the preferred form, it is desirable to start and stop the reciprocation automatically in timed relation with the movement of the Work driving Wheel to and from an operating position. A downwardly extending prcjection 23|! of the lever |25 is connected by means of a stud 23| with a link 232 which is connected to an arm 233 formed integral with the yoked member 225. It will be apparent from this disclosure that when the lever |25 is rocked in a clockwise direction to shift the control valve 2|3 and thereby cause a movement of the work rotating wheel 55 to an inoperative position, the clutch 223 will be disengaged, thereby stopping the reciprocation of the tables I3 and The shaft 200 which simultaneously reciprocates the tables and |2 in opposite directions is driven in a similar manner. A V-belt 250 transmits power from the motor pulley 65 to a V-pulley 25| mounted on a rotatable sleeve 252 which is in turn rotatably supported on a rotatable shaft 253. The shaft 253 is journalled in suitable antiefriction bearings 254 and 255. A friction disk clutch 256 is interposed between the pulley sleeve 252 and the shaft 253. The shaft 253 is provided at its outer end with a V-grooved pulley 251 which is connected by a V-belt 258 with a pulley 259 mounted on the shaft 200. A clutch shifting member 260 associated with the clutch 256 is operatively connected in a manner similar to that described in connection with the clutch 223 so that when the control lever |45 is moved to cause a movement of the work driving wheel 15, either toward or from an operating position, the clutch 256 will be actuated so as to start the simultaneous reciprocation of the tables andl I2 in opposite directions when the driving wheel 15 is moved into engagement with the armature r40 of the shaft 2|, or is disengaged when the work driving Wheel 15 is moved out of engagement with the armature 46 after the polishing operation has been completed to stop the reciprocatory movement of the tables and I2.

Automatic start and stop work rotation In order to facilitate loading of the machine, it is desirable to provide an automatic mechanism whereby movement of the arms 59 and 19 toward or from an operating position serves to actuate the clutches 12 and 13, respectively, to start or stop the rotation of the work driving wheels 55 and 15, respectively. A lever 265 is fixedly mounted on the inner end of the shaft 15 so that in effect the yoked member 14 and the arm 265 form a bell crank lever. A link 266 is connected to the outer end of the arm 265 by means of a stud 261. The upper end of the link 266 is provided with an elongated slot 268. A stud 269 xedly mounted on the arm 59 rides in the elongated slot 268 and serves when the work driving wheel 55 is moved upwardly to an inoperative position to rock the arm 265 and the yoke 14 so as to disengage the clutch 12 and thereby stop the rotation of the wheel 55 automatically when it is moved to an inoperative position.

Similarly, an arm 210 is flxedly mounted on the inner end of the shaft 92 so that in effect it forms a bell crank lever with the clutch shifting yoke 9|. A link 21| is connected by a stud 212 with the lever 2519. The upper end of the link 21| is provided with an elongated slot 213. A stud 214 lixedly mounted on the arm 19 rides within the elongated slot 13 and serves when the work driving wheel l5 is moved downwardly into an operating position to rock the lever 210 and thereby shift the yoke 16 to engage the clutch member 13 and start the rotation ofl the work driving wheel as it approaches an operating position. The rotation of the wheel 15 is stopped when it is moved to an inoperative position out of contact with the work piece being polished.

A modified form of work supporting member has been illustrated in Fig. 8. For certain types and sizes of work. it may be desirable to provide a concave work supporting surface for supporting the abrasive strip instead of providing a pair of spaced rollers. As illustrated in Fig. 8, an abrasive supporting member |60 is provided with an upper concave partial cylindrical surface |6| overu which extends a continuous strip of abrasive paper |63. The curvature of the surface |6| preferably is the same as or of a greater radius than that of the finished work piece. The abrasive paper |63 passes over an idler roller |64 and an idler roller |65 and may be wound up by means of a pawl and ratchet mechanism, as above described in connection .with the disclosure in Fig. 2.

In polishing certain types of work, it may be desirable to utilize a bonded abrasive wheel in# stead of a flexible abrasive element, as shown in Figs. 1 to 7 inclusive. As shown in the modification illustrated in Fig. 9, an 4abrasive supporting member 235 serves as a support for a pair of bonded abrasiveA wheels 236 and 231. These wheels are arranged with their axes parallel to each other on studs or spindles 238 and 239 and are spaced apart by a sufficient distance so that they form spaced abrasive supports for a work piece 246. A work driving wheel 24| is rotatably supported on a pivotally mounted support 242 and is arranged to be moved into frictional engagement with the Work piece 240 to rotate the same relative to the abrasive wheels 236 and 231 for a polishing operation. During the polishing operation, the abrasive wheels 236 and 231 and the support 235 therefor are reciprocated longitudinally or axially in a manner similar to that shown in Figs. 1 to 7 inclusive.

In order to provide a fresh abrading surface for each polishing operation, a suitable mechanism is provided for normally holding the abrasive wheels 236 and 231 against rotation. This mechanism is preferably in the form of an in dexing mechanism which is actuated automatically to index the abrasive wheels 236 and 231 a slight amount each time the work driving wheel 24| is moved toward and from an operating position. 'I'his mechanism comprises a gear train including a gear 243 which is mounted to rotate the wheel 236, an intermediate gear 244 which is rotatably supported on the supporting member 235, and a gear 245 which is arranged to rotate the wheel 231.

A ratchet wheel 246 is mounted to rotate with the gear 245 and wheel 231. A pawl 241 is pivotally mounted onone arm of a bell crank lever 248, which lever is pivotally supported on the spindle 239. When the driving wheel is moved to an operating position, the pivotally mounted arm 242 which supports the driving wheel 24| moves a rod 249 downwardly to rock the bell crank lever 248 in a clockwise direction, causing the index pawl 247 to ride idly over the ratchet wheel 245. After the polishing operation has been completed and the work driving wheel 24| is moved upwardly to an inoperative position, the released compression of a spring pressed plunger 250 serves to rock the bell crank lever 248 in a counterclockwise direction, thereby causing the pawl 241. to rotate the ratchet wheel 246 and thereu by index the wheel 231 a slight amount to present a new abrasive surface for the next work piece. At the same time, the rotary indexing movement is transmitted from the wheel 23'! through the gears 245, 244 and`243 to rotate the abrasive wheel 236 a similar amount to present a new abrasive surface for the next polishing operation. It will be readily apparent that the pawl and ratchet mechanism may be so arranged and adjusted that the wheels may be indexed by small amounts merely sufficient to present a fresh abrading contact with the work piece on successive polishing operations.

The operation of this improved polishing machine will be readily apparent from the foregoing disclosure. An armature shaft 22 is placed in position with the bearing portions 35 and 36 resting on the strips of abrasive paper 45a and 45, respectively, thus depressing the paper and causing it to wrap around a portion of the bearn ing surface. The control lever |25 is then rocked in a clockwise direction to shift the control Valve ||3 so as to cause the work driving wheel 55 to rock into the positionvillustrated in Fig. 2. Movement of the work driving wheel 55 into an operating position automatically shifts the clutch 12 to start the rotation of the wheel v55. The shifting of the control lever |25 to start the appreaching movement of the wheel 55 :to an operating position .also serves through the link 232 to actuate the .clutch 223 Yto produce a simultaneousy reciprocation 'ofl the tables I3 and I4 in oppositey directions soY as to cause a relative reciprocation between the work piece and the abrasive paper during rotation of thework Apiece y on said paper.

It will thus be seen ythat `there hasbeen prof r vided .by this; inventiomapparatus in which ,the various objects hereinabovey set forth together with many thoroughly `practical, advantages are successfully achieved. .As many posv sible embodiments may be madeof the `above invention Yand as manychanges mightbe made in the embodiment labove set-forth, it is to be understood that all matter hereinbefore set forth or shown in the accompanying drawings is toghe interpreted as illustrative and not ina limiting sense.

, I claim:- f

1. In a polishing machine, a continuous strip of flexible abrasive material, a supporting member having a partial cylindrical work supporting surface thereon to support said abrasive so as` to form an abrasive support for a work piece to be polished, a rotatable work driving wheel which is arranged frictionally to engage and rotate a. work piece, means to rotate said driving wheel, a pivotal support for the driving Wheel,

toggle levers to swing said support, and means including a iiud pressure piston and cylinder which are operatively connected to actuate said toggle levers so as to swing said support and driving wheel to and from an operating position.

2. In a polishing machine, a continuous strip of abrasive material, a work supporting member having a concave surface thereon to support said abrasive element so as to form an abrasive support for a work piece to be polished, a ro tatable work driving Wheel which is arranged frlctionally to engage and rotate a work piece, a pivotally mounted arm to support said wheel, and means including a fluid pressure operated piston and cylinder which are operatively con nected to swing said arm.

3. In a polishing machine, a continuous flexible abrasive element, a pair of spaced parallel rollers to support said abrasive so as to form an abrasive support for a work piece to be polished, a rotatable work driving wheel which is arranged frictionally to engage and rotate a work piece, and means including a toggle lever mechanism to move said friction wheel toward and from said work piece.

4. In a polishing machine, a longitudinally reciprocable slide, a pair of spaced parallel rollers on said slide, a strip of flexible abrasive material on said rollers which is arranged to support a work piece for a polishing operation, a rotatable driving wheel which is arranged frictionally to engage and rotate a work piece supported thereon, means to move said friction wheel toward and from said work piece, and means relatively to reciprocate said rollers and abrasive strip during a polishing operation.

5. In a polishing machine, a pair of longitudinally reciprocable slides. a pair of spaced work supporting members on each of said slides, a flexible abrasive element passing over each of said supporting members which are arranged to form an abrasive support for spaced cylindrical portions on a work piece during a polishing operation, means including a rotatable driving wheel which is arranged frictionally to engage and rotate a work piece supported thereon, and means simultaneously to reciprocate said slides in opposite directions to cause a relative longitudinal movement between the abrasive element and work.

6. In a polishing machine, a longitudinally reciprocable slide; a work supporting member on said slide, .a continuous flexible abrasive element which passes over said supporting member and serves to polish a workpiece supported thereon,

a rotatable driving wheel for a work piece, means l including a clutch Vto rotate saidwheel, means.

to move said frictional driving wheel into or away from operative` contact with the work. and means actuated thereby tn operate said clutch to start the rotation of the friction wheel when it is moved into an operating position.

7. In a polishingmachine, a longitudinally reciprocable slide, a work supporting member thereon, a continuous flexible abrasive element passing over said supporting member and serving'as a support to polish a work piece supported thereon, a friction driving Wheel 'arranged to engage the periphery of a work piece to rotate the same,

means including a clutch to rotate said wheel.

start the rotation of the wheel toward an operating position.

8. In a polishing machine, a longitudinally reciprocable slide, a work support thereon, a ilexible abrasive element passing over said Work support and arranged to support and polish a Work piece which is supported and rotated thereon, a rotatable work driving wheel which is arranged to engage and rotate a work piece, means to reciprocate said slide to cause a reciprocatory movement of the abrasive support for the work piece during rotation thereof, means including a iiuid pressure operated piston and cylinder to move said wheel toward and from an operative position, a manually operable control valve to control the admission of iiuid to said cylinder, and means including a clutch actuated by and in timed relation with movement of said valve to start the reciprocation of the slide when the wheel is moved toward an operating position.

9. In a polishing machine having a longitudinally reciprocable slige, a work supporting member, a iiexible abrasive element passing over said member and arranged to support and polish a work piece which is supported and rotated thereon, means including a friction driving wheel which is arranged frictionally to engage and rotate a work piece, a pivotal support for said wheel, means including a clutch to rotate said wheel, means including a piston and cylinder to move said pivotal support to cause the wheel to move toward or from an operating position, a clutch actuating mechanism operated by movement of said pivotal support to engage said clutch when the wheel is moved toward an operating position, means to reciprocate said slide to produce a relative longitudinal movement between the abrasive element and said work piece, a manually operable control lever and a valve to control the admission of fluid to said cylinder, and a clutch which is actuated by said lever to start the reciprocation of said slide when the driving Wheel is moved into an operating position.

10. In a polishing machine, a pair of spaced longitudinally reciprocable slides, a work supporting member on each of said slides, a continuous exible abrasive element passing over each of said supports which are arranged simultaneously to support and polish spaced portions on a cylindrical work piece, a rotatable frictional driving wheel arranged to engage and rotate a work piece, means including a manually operable lever to move said frictional wheel to and from an operating position, means simultaneously to when itis moved reciprocate said slides in the opposite direc-tion,

and means including a `clutch actuated by said control lever to start reciprocation` of said slides when the friction wheel is moved into an operating position.

11. In a polishing machine for polishing cylindrical work, a longitudinally reciprocable table, a pair of spaced rollers on said table, a rotatably mounted spool having a continuous strip of abrasive paper thereon, said abrasive paper passing over said spaced rollers, a spool located below said first spool and arranged to wind up used abrasive paper, a rotatable work driving wheel Which is arranged frictionally to engage and rotate a work piece during a polishing operation, and means including a toggle lever mechanism to move said friction wheel toward and from said work piece. l

12. In a polishing machine, a longitudinally reciprocable table, a pair of spaced rollers on said table, a. roll of strip abrasive material the strip of which is extended over said rollers, nid spaced rollers and abrasive being arranged simultaneously to support and polish a cylindrical work piece, a rotatable roller upon which the used portion of the strip is wound, a rotatable work driving wheel which is arranged frictionally to engage and rotate the work piece'during the griding operation, and means actuated automatically by movement of said driving wheel to and from an operative position intermittently to rotate said second roller automatically Ito advance the strip of abrasive material.

13. In a polishing machine, a longitudinally reciprocable slide, a rotatable Work driving wheel which is arranged frictionally to engage and rotate a work piece, means to reciprocate said slide, means to move said wheel toward and from sai-d slide, a Work supporting member on said slide, a roll of strip abrasive material the strip of which extends over said work support to form an abrasive support for the work pieceto be polished, a rotatable roller upon which the used portion of/said strip is wound, a pawl and ratchet mechanism to rotate said second roller, means actuated by movement of said driving Wheel toward an operating position to move said pawl idly over the ratchet wheel, and a spring pressed plunger which is rendered operative each time said driving wheel is moved to an inoperative position for drawing said abrasive strip over said work support a predetermined amount.

' 14. In a polishing machine, a pair of normally non-rotatable spaced abrasive wheels to form an abrasive support for a work piece to be polished, a rotatable work driving wheel which is arranged frictionally to engage and rotate a Work piece, a pivotal support for said driving Wheel, means to rotate said driving wheel, and means to swing saidx support and driving wheel toward and from an operating position.

15. In a polishing machine, a pair of normally non-rotatable spaced abrasive wheels to form an abrasive support ifor a work piece to be polished, a rotatable work driving wheel which is arranged frictionally to engage and rotate a Work piece, means to rotate said driving wheel, means to move said driving wheel toward and from an operating position, and means to recprocate said abrasive wheels longitudinally relative to saiddriving wheel while the driving wheel is in an operative position.

16. In a polishing machine, a pair of normally non-rotatable spaced abrasive wheels to form an abrasive support for a work piece to be polished, a rotatable work driving wheel which is arranged frictionally to engage and rotate a work piece, means to rotate said driving wheel, means to move said Work driving wheel toward and from an operative position, and means including an indexing mechanism simultaneously to index said wheels to' present a fresh abrasive surface when said driving wheel is moved to an inoperative position.

1'7.- In a polishing machine, a pair of normally non-rotatable spaced abrasive wheels to form an abrasive support for a Work piece to be polished, a rotatable work driving wheel which is arranged frictionally to engage and rotate a Work piece, means -to rotate said driving wheel, means to move said work driving wheel toward and from an operative position, means to reciprocate said abrasive wheels axially when the driving wheel is in an operating position, and means-including an indexing mechanism automatically and simultaneously to index said abrasive wheels to present a fresh abrasive surface for each successive polishing operation.

18. In a polishing machine, a pair of longitudinally reciprocable slides, an abrasive work support and polishing device on each of said slides simultaneously to support .and polish spaced cylindrical portions on a work piece, a rotatable work driving wheel which is arranged frictionally to engage and rotate the work piece, and means simultaneously to reciprocate said slides in opposite directions so as to cause a relative longitudinal movement between the abrasive work support and the work piece.

19. In a polishing machine, a pair of longitudinally reciprocable slides, a work supporting member on each of sai-d slides, a continuous ilexible abrasive element passing over each of said supporting members simultaneously to support and polish spaced cylindrical portions on a work piece, a rotatable driving wheel which is arranged 4frictionallv to engage and rotate a work piece,

`and means simultaneously to reciprocate said slides in opposite directions so as to cause a relative longitudinal movement between the abrasive element and work.

20. In a polishing machine, a pair of longitudinally reciprocable slides, an abrasive work supporting and polishing member on each of said slides simultaneously to support and polish spaced cylindrical portions on a work pie, a rotatable work driving wheel which is arranged frictionally to engage and rotate a work piece, means to move said driving wheel into or away from engagement with the work piece, means simultaneously to reciprocate said slides in opposite directions to cause a relative longitudinal movement between the abrasive element and work, and means including an indexing mechanism simultaneously to index said abrasive work supporting and polishing members when the work driving wheel is moved to an inoperative position.

HERBERT S. INDGE. 

